Winder



D. C. CRONIN Oct. 10, 1967 WINDER Filed Sept. 17, 1955 11\"VE./\"'TOR: 090/766 C 00/707 gay WWTORNEYS United States Patent 3,346,209 WlNDER Dennis C. (Ironin, Rockton, 11]., assignor to Beloit Corporation, Beloit, Wis, a corporation of Wisconsin Filed Sept. 17, 1965, Ser. No. 483,091 8 Claims. (Cl. 242-66) ABSTRACT OF THE DISCLOSURE A winder for controlling the compactness of a roll of sheet material which includes a pair of winding drums disposed for receiving the enveloped roll thereon and a tensioning roll. A rider roll having a variable position is employed for controlling the pressure in the nips between the winding drums and the enveloped roll. The tensioning roll may also be movable or a differential of air pressure may be employed across the nips to control the compactness of the enveloped roll.

This invention relates generally to a method and apparatus for controlling the hardness of a wound roll of sheet material and more particularly to a novel method and apparatus for controlling the degree of compactness of a sheet of material as it is being wound into a roll by controlling the nip pressures between the winding drums and the enveloping roll. This invention has particular application in the winding of a paper Web on a core, however, it is to be understood that the present invention may be employed for winding any material into roll form. The present invention may be employed in any winder mechanism for enveloping a sheet material on a core.

One of the problems associated with the enveloping of a sheet of material on a core to form a roll of that material is that of controlling the compactness of the roll and maintaining it uniform throughout its entire diameter so as to eliminate wrinkling, folding and other defects. Heretofore, it has been one of the practices in the art to control the pressure in the nips between a roll and a winding drum solely by means of a rider roll. However, as the weight of the roll increased with the sheet material being wound thereon, the rider roll control became ineffective and the compactness of the roll could not be maintained uniformly. That is, after the roll reached a predetermined diameter, the rider roll would have to be completely lifted therefrom allowing the weight of the enveloped roll to govern its compactness. As the roll increased further in diameter, the weight also increased causing greater compactness of the roll and, consequently, nonuniform compactness across the diameter of the roll.

Another problem encountered in controlling the compactness of an enveloping roll is inherent in the structure of the winding apparatus. For instance, in such prior art winders, the enveloping roll was supported on one, or possibly two, winder drums and the sheet material was supplied directly over the winding drums to the enveloping roll without any appropriate tensioning means for the sheet.

In addition, the prior art winders do not offer suflicient and adequate means for lifting the enveloping roll when its weight is greater than that required for proper nip pressure. Such structures are required after the rider roll is removed and after the weight of the roll has increased beyond that required for proper nip pressure. If these structures are not provided in a winder or are not adequate, uniform compactness of the roll cannot be achieved.

It is, therefore, an object of the present invention to provide a method and apparatus for enveloping a web material on a core with a uniform compactness across the entire diameter thereof.

Another object of the present invention is to provide a method and apparatus for enveloping a web material on a core wherein the nip pressure between the enveloped roll and a winding drum is maintained constant during the entire enveloping process.

Still another object of the present invention is to provide a method and apparatus for winding a web material on a core wherein a pressure differential is maintained between the space on one side of the enveloped roll and the space on the other side of the enveloped roll such that the roll is wound or enveloped with a uniform compactness.

Yet another object of the present invention resides in the provision of a tensioning roll in combination with a pair of winding drums to provide a uniform compactness in a wound or enveloped roll.

And still another object of the present invention resides in the provision of an air source variable between a lower than standard atmospheric pressure to higher than standard atmospheric pressure and connected to control the nip pressure between the developing roll and at least one winding drum.

Yet another object of the present invention resides in the provision of a source of vacuum connected in the space between an enveloping roll and a pair of winding drums to increase the nip pressure between the roll and the drum while the enveloped roll is relatively small sized.

Another object of the present invention resides in the provision of a source of air pressure connected in the space between an enveloping roll and a pair of winding drums to reduce the nip pressure therebetween while the enveloped roll is relatively large sized.

These and other objects, features and advantages of the present invention will be more fully realized and understood from the novel concepts of the present invention which generally include controlling the nip pressure between an enveloping roll and a winding drum to within a relatively small predetermined range while the roll is being enveloped. In particular, this nip pressure may be accurately controlled by providing a closed space between the enveloping roll and two Winding drums and varying the atmospheric pressure in that space from less than standard atmospheric pressure to greater than standard atmospheric pressure. That is, a pressure dilferential between the enclosed space and the space external of the enveloped roll and winding drums can accurately control the nip pressure between the enveloping roll and the two winding drums.

The novel concepts of the present invention will be more fully realized and understood, however, from the following detailed description when taken in conjunction with the accompanying drawings wherein:

FIGURE 1 is a diagrammatic view of one embodiment of the present invention at the start of a new roll being enveloped on a core;

FIGURE 2 is a diagrammatic view of the present invention as the enveloped core reaches a relatively medium size;

FIGURE 3 is a diagrammatic view of the present invention as the enveloped roll reaches a maximum diameter for completion of the roll;

FIGURE 4 illustrates diagrammatically still another embodiment of the present invention at the start of a new roll; and

FIGURE 5 illustrates diagrammatically still another embodiment of the present invention at the start of a new roll.

Like reference numerals throughout the various views of the drawing are intended to designate the same or similar structures.

As shown on the drawings:

With reference to the drawing and in particular detail to FIGURE 1, there is shown one embodiment of the present invention at the start of a new roll being enveloped on a core. A web material such as paper or the like is passed over a first winding drum 12, over a tensioning roll 14, over a second winding drum 16, and onto a core 18 to form an enveloped roll 20. Winding drums 12 and 16 are driven by suitable means (not shown). The enveloped roll 20 forms a nip 22 with the first winding drum 12 and a nip 24 with the second winding drum 16. The amountof pressure applied at the nips 22, 24 determines the degree of compactness of the roll 20 as it is being enveloped.

During the start of the enveloping process when the enveloped roll is relatively small sized, the weight of the enveloped roll is not usually sufficient to create the required pressure in the nips 22, 24 to compact the roll 20 to the desired degree. A rider roll 26 is mounted on an arm 28 which is pivotally mounted about a point 30 to apply a downward force as indicated by the arrow 32 onto the roll 20 to increase the pressure in the nips 22, 24. The force applied by the rider roll 26 to the enveloped roll 20 may be accurately controlled by any means as indicated diagrammatically by the arrow 34 directed against the arm 28. Pressure-sensing devices (not shown) may be employed for providing an indication of the pressures in the nips 22, 24 to control the amount of force applied to the enveloped roll 21) by the rider roll 26.

As the enveloped roll 20 increases in size and consequently in weight, the force of the rider roll thereon is decreased since the pressure in the nips 22, 24 is in part provided by the weight of the roll 20 on the core 18. When the roll 20 has reached a sufficient diameter such that its own weight is sufficient to maintain required pressure in the nips 22, 24, the rider roll 26 is removed from the roll 20. The correct amount of tension is maintained in the web 10 being enveloped on the core 18 by the tension roll 14 which is movable as indicated by the doubleheaded arrow 36.

It is also practical to employ the structure illustrated in FIGURE 1 without any control upon the amount of force applied by the rider roll to the enveloped roll 20. That is, adequate results are obtained if the rider roll 26 is simply placed in engagement with the enveloped roll 20 and, other than its own weight, no control over the amount of force which is applied to the enveloped roll 20 is required. In such a configuration, uniformity of compactness of the enveloped roll 20 may be achieved by positioning the tension roll to maintain a predetermined tension on the web 10 as it is being enveloped on the roll 20.

When the size of the roll 20 has increased sufficiently so that its own weight will provide the proper pressure required in the nips 22, 24, the rider roll 26 is removed from its contact with the roll 20. Such an arrangement is illustrated in FIGURE 2 wherein the web 10 passes over the drum 12, the tensioning roll 14, the drum 16, and Onto the enveloped roll 20. The nips 22, 24 are maintained within the prescribed range of pressure only by 4 the weight of the roll 20 as illustrated in FIGURE 2. However, if it is desired to control the compactness of the roll 20 within a more limited range, control of the web tension may be provided by positioning the tensioning roll 14 as indicated by the arrow 36.

As the size of the roll 20 increases beyond the point where the nip pressures are greater than that desired, means are provided for lifting the roll 20 and reducing the nip pressures. One preferred configuration for providing such a result is illustrated in FIGURE 3 wherein a source of air pressure 38 is connected to a space 40 between the winding drums 12, 16, the tensoning roll 14, and the roll 20. This connection of the air pressure source 38 into the space 40 between the drums 12, 16 and the roll 20 is indicated diagrammatically by the line 42.

Adequate sealing means such as a space enclosure indicated diagrammatically by the dashed line 41 is provided at each end of the winding drums 12, 16 to seal the space 40 adequately to allow only a minimum amount of air leakage from the space 40. Slight leakage at the ends of the apparatus and through slits which may be provided in the sheet material may be advantageous resulting in less wrinkling and tighter edges of the sheet material. The air pressure source 38 is variable and as the weight of the roll 20 increases, the air pressure provided to the space 40 is increased proportionally to relieve the roll weight on the nips 22, 24. In this manner, the nip pressures are maintained relatively constant to provide uniform compactness of the roll 20 as it is being enveloped. While air pressure is being supplied to the space 40, it may be desirable to position the tensioning roll 14 as indicated by the arrow 36 to control the tension in the sheet material as it passes over the winding drums 12, 16 onto the roll 20. Such movement of the tensioning roll 14 will not interfere with the air pressure in the space 40- if the sealing mean-s is provided adjacent the edges of the sheet 10 as it passes over the drums 12, 16 and the tensioning roll 14.

It can be readily appreciated that an increase in the air pressure in the space 40 provides a lifting action on the roll 20 to relieve pressure created in the nips 22, 24 by the weight of the roll 20. By accurately controlling the air pressure source 38 and, consequently, the air pressure in the space 40, the compactness of the roll 20 is accurately controlled. Furthermore, by positioning of the tensioning roll 14, tension of the sheet 10 is accurately controlled to provide still another control over the compactness of the roll 20. These two functions can be employed cit-her separately or in combination with one another to provide the required compactness of the roll 20.

The apparatus illustrated in FIGURE 1 employed the weight of the roll 20, the weight of the rider roll 26, and the additional force indicated by the arrow 34 to control the pressures in the nips 22, 24 and thereby controlling compactness of the roll 20. However, it is possible to control the nip pressures by means other than the rider roll 26. Two alternate methods of controlling the nip pressures when the roll 20 is relatively small sized are illustrated in FIGURES 4 and 5.

As illustrated in FIGURE 4, the source of air pressure 38 is connected to the space 40 and provides a less than standard atmospheric pressure within the space 40. In the embodiment of FIGURE 4, therefore, the air pressure source 38 may be a vacuum pump which performs to evacuate the space 40 to provide the less than standard atmospheric pressure therein. Therefore, a pressure differential is realized between the space 40 and the space external of the apparatus to increase the pressure in the nips 22, 24 to the desired amount. As the size of the roll 20 increases, pressure in the nips 22, 24 is primarily attained from the weight of the roll 20 and, consequently, the pressure difierential may be decreased to maintain the nip pressures constant. If desired, the apparatus illustrated in FIGURE 4 may be provided with additional control over the compacting of the roll 20 by positioning of the U tensioning roll 14 as previously described with respect to the preceding figures.

As the size of the roll 20 increases, the vacuum produced by the air pressure source 38 is reduced until the weight of the roll 20 is sufiicient to maintain the nip pressures within the desired range. As the size of the roll 20 increases still further, the air pressure source 38 provides a greater air pres-sure in the space 40 than in the surrounding space. Therefore, it can be readily appreciated that a pressure differential between the space 40 and the surrounding space externally of the apparatus which varies from less than standard atmospheric pressure to greater than standard atmospheric pressure will accurately control the compactness of the roll 20 from the beginning of the enveloping process to its completion.

As illustrated in FIGURE 5, the compactness of the roll 20 at the start of the enveloping process may be accurately controlled by controlling the position of the tensioning roll 14. By increasing the tension on the sheet by movement of the tensioning roll 14 in a downward direction, a force is applied through the sheet 11} to the roll in a downward direction to increase the pressure in the nips 22, 24. If the tensioning roll 14 is moved in an upward direction, however, the tension in the sheet 10 will be relieved and the force exerted on the roll 20 through the sheet 10 will be decreased. Therefore, by positioning of the tensioning roll 14, the pressures in the nips 22, 24 can be accurately control-led and the compactness of the roll 20 can be maintained constant throughout the entire enveloping process.

From the above description of the figures, it can be readily appreciated that the compactness of the roll 20 can be accurately controlled by a force transmitted through the sheet 10 corresponding to the tension therein or by a pressure differential between the space 40 and the space external of the apparatus. It can also be appreciated that the nip pressures can be controlled by a combination of the above two mentioned methods. By employment of one or both of these methods, the rider roll 26 illustrated in FIGURE 1 can be eliminated from the winding operation.

In one exemplification of the present invention, the roll 20 may be enveloped to a diameter of between 5 to inches at the end of the cycles illustrated in FIGURES 1, 4, and 5; to a diameter of approximately 25 inches in the cycle illustrated in FIGURE 2; and to a diameter of 50 inches at the end of the cycle illustrated in FIGURE 3. In the exemplification illustrated in FIGURE 3, variable air pressures of 23 p.s.i. were preferably employed. The vacuum produced in the space of the exemplification illustrated in FIGURE 4 was in actual practice of the invention preferably in the range of 1015 in. Hg and variable as the roll 20 increased in size.

The principles of the invention explained in connection with the specific exemplifications thereon will suggest many other applications and modifications of the same. It is accordingly desired that in construing the breadth of the appended claims they shall not be limited to the specific details shown and described in connection with the exemplifications thereof.

1 claim:

1. The method of controlling the compactness of a roll forming at least one nip with a winding drum, comprising the steps of (a) applying a fluid pressure force by direct contact between the fluid and the roll to maintain a constant pressure in the nip,

(b) changing the amount of the force applied as the size of the roll changes to maintain the constant pressure in the nip, and

(c) changing the direction of the force applied as the size of the roll increases to and beyond a size which will sustain the pressure in the nip at the constant pressure.

2. The method of controlling the compactness of a roll forming at least one nip with a winding drum, comprising the steps of (a) applying a fluid pressure force by direct contact between the fluid and the roll to maintain a predetermined pressure in the nip while the roll is relatively small sized, and

(b) removing the force and maintaining the predetermined pressure in the nip by the weight of the roll while the roll is relatively large sized.

3. The method of controlling the compactness of a roll forming at least one nip with a winding drum, comprising the steps of (a) applying a fluid pressure force by direct contact between the fluid and the roll to maintain a predetermined pressure in the nip while the roll is relatively small sized,

(b) removing the force and maintaining the predetermined pressure in the nip by the weight of the roll While the roll is relatively medium sized, and

(c) then lifting the roll to maintain the same predetermined pressure in the nip while the roll is relatively large sized.

4. The method of controlling the compactness of a roll of sheet material while it is being enveloped from a supply and which forms at least one nip with a winding drum, comprising the steps of (a) tensioning the sheet material adjacent the roll in a direction to increase the pressure in the nip, and

(b) changing the length of the sheet between the supply and the roll to thereby change the amount of tension in the sheet material as the size of the roll changes to maintain the pressure in the nip relatively constant.

5. The method of controlling the compactness of a roll being enveloped by a sheet material and forming at least two nips with a pair of winding drums, comprising the steps of (a) establishing a pressure differential between the space on one side of the nips and the space on the other side of the nips to provide a fixed pressure in the nips,

(b) changing the pressure differential between the spaces to maintain the pressure in the nips fixed as the size of the roll changes, and

(c) tensioning the sheet material adjacent the roll to further maintain the pressure in the nips fixed as the size of the roll changes.

6. An apparatus for controlling the compactness of an enveloped roll of sheet material, comprising (a) a pair of winding drums each disposed in intimate contact with the roll and forming respective nips therewith;

(b) a tensioning roll mounted between said winding drums and spaced from the enveloped roll, the sheet material being enveloped on the roll passing successively over one of said winding drums, the tensioning roll, the other of said winding drums, onto the roll;

(c) means enclosing the space between said winding drums, said tensioning roll, and the enveloped roll, and

(d) means providing a pressure differential between the enclosed space and the space external thereof.

7. An apparatus for controlling the compactness of a roll of sheet material comprising (a) a pair of winding drums each disposed in intimate contact with the roll and forming respective nips therewith,

(b) means for tensioning the sheet material prior to its being enveloped on the roll, the sheet material passing over a first one of said winding drums to said tensioning means and extending from said tensioning means over a second one of said winding drums onto the roll, and

(c) means for producing a fluid pressure differential between the space on one side of said nips and the 7 8 space on the other side of said nips, which pressure (0) means enclosing the ends of the sheet material to difierential is relative to the size of the roll. define a closed space between said Winding drums, 8. An apparatus for controlling the compactness of an d tensioning r and the enveloping roll; and enveloping roll of sheet material comprising maans for PTeSSuTiZing Said closed p (a) a pair of Winding drums supporting the enveloping 5 roll thereon;

(b) a tensioning roll between said Winding drums; the UNITED STATES PATENTS sheet material passing successively over one of sai 1,966,331 7/1934 Cameron 242-6o winding drums, said tensioning roll, and the other of said winding drums to the enveloping roll, 10 WILLIAM BURDEN, Primary Examiner References Cited 

1. THE METHOD OF CONTROLLING THE COMPACTNESS OF A ROLL FORMING AT LEAST ONE NIP WITH A WINDING DRUM, COMPRISING THE STEPS OF (A) APPLYING A FLUID PRESSURE FORCES BY DIRECT CONTACT BETWEEN THE FLUID AND THE ROLL TO MAINTAIN A CONSTANT PRESSURE IN THE NIP, (B) CHANGING THE AMOUNT OF THE FORCE APPLIED AS THE SIZE OF THE ROLL CHANGES TO MAINTAIN THE CONSTANT PRESSURE IN THE NIP, AND (C) CHANGING THE DIRECTION OF THE FORCE APPLIED AS THE SIZE OF THE ROLL INCREASES TO AND BEYOND A SIZE WHICH WILL SUSTAIN THE PRESSURE IN THE NIP AT THE CONSTANT PRESSURE. 